AI Security Engineer in London

A career at Janus Henderson is more than a job, it’s about investing in a brighter future together. Our Mission at Janus Henderson is to help clients define and achieve superior financial outcomes through differentiated insights, disciplined investments, and world-class service. We will do this by protecting and growing our core business, amplifying our strengths and diversifying where we have the right.

Our Values are key to driving our success, and are at the heart of everything we do:

• Clients Come First - Always
• Execution Supersedes Intention
• Together We Win
• Diversity Improves Results
• Truth Builds Trust

If our mission, values, and purpose align with your own, we would love to hear from you!

Your opportunity: The AI & Automation Security Engineer is a hands-on role for engineers passionate about both AI and cybersecurity. This position has a dual focus: first, securing business AI systems including AI-enabled applications, LLM models, agents, and supporting platforms across their full lifecycle. Second, leveraging AI and automation to transform and scale the security function, through risk-based vulnerability management, alert enrichment, workflow orchestration, and CI/CD checks.

Whether your background is in security engineering with AI experience or as an AI engineer eager to deepen your security expertise, you will collaborate across teams, applying and expanding your skills to deliver robust, production-ready protections and innovative security solutions at scale, with an emphasis on business impact and responsible practices.

What to expect when you join our firm:

• Hybrid working and reasonable accommodations
• Excellent Health and Wellbeing benefits including corporate membership to Wellhub
• Paid volunteer time to step away from your desk and into the community
• Support to grow through professional development courses, tuition/qualification reimbursement and more
• Maternal/paternal leave benefits and family services
• All employee events including networking opportunities and social activities
• Lunch allowance for use within our subsidised onsite canteen

Must have skills:

• Solid grasp of security engineering fundamentals and familiar with common attack vectors and defence techniques.
• Proven ability to build and deploy automation using code, APIs, and orchestration tools (e.g., Python, workflow engines, SOAR platforms).
• Practical experience with AI/LLM systems and automation, including prompt engineering, retrieval augmented generation (RAG), function-calling, or agent-based tools.
• Skilled at integrating security logs, AI models, and platform components into cohesive pipelines.
• Effective communicator and collaborator, able to prioritise security risks based on business impact.
• Demonstrated initiative, ownership, and adaptability in fast-paced, evolving environments.
• Ability to work with senior stakeholders across infrastructure, engineering and risk to translate AI risks into actionable controls and standards.
• Leading design reviews, threat modelling and targeted implementation for critical AI initiatives.

Nice to have skills:

• Experience with vulnerability management or risk-based threat prioritisation.
• Knowledge of securing AI agents or agentic workflows, including scoped permissions and approval processes.
• Able to identify and put guardrails to prevent AI-specific security risks such as prompt injection, model hijacking, data leakage from LLM outputs, or configuration drift caused by AI assistants.
• Ability to automate response workflows, enrich incident data, and assist with triage.
• Awareness of frameworks like NIST AI RMF, OWASP for GenAI, or MITRE ATLAS.
• Mentor security engineers on AI-related security challenges based on existing and emerging AI risk.

Supervisory responsibilities: No

Potential for growth: Regular training, Continuing education courses.

You will be expected to understand the regulatory obligations of the firm, and abide by the regulated entity requirements and JHI policies applicable for your role. At Janus Henderson Investors we’re committed to an inclusive and supportive environment. We believe diversity improves results and we welcome applications from candidates from all backgrounds. Don’t worry if you don’t think you tick every box, we still want to hear from you!

We understand everyone has different commitments and while we can’t accommodate every flexible working request we’re happy to be asked about work flexibility and our hybrid working environment. If you need any reasonable accommodations during our recruitment process, please get in touch and let us know.

Annual Bonus Opportunity: Position may be eligible to receive an annual discretionary bonus award from the profit pool. The profit pool is funded based on Company profits. Individual bonuses are determined based on Company, department, team and individual performance.

Benefits: Janus Henderson is committed to offering a comprehensive total rewards package to eligible employees that includes competitive compensation, pension/retirement plans, and various health, wellbeing and lifestyle benefits.

Janus Henderson Investors is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability or veteran status. All applications are subject to background checks.